Tech Guide
TV sets

The technology behind the screens

Televisions all have flat screens these days, as seen in the sales rooms of your specialist dealer. But on closer inspection, there are some big differences. The colors are brighter and more natural on some screens. Black appears richer and darker, and scenes have more contrast. Some displays are so thin that they can hang on the wall like posters. Much of this has to do with the screen technology.

Traditional: LCD

Most televisions have a liquid crystal display (LCD). The pixels are illuminated by LEDs behind the screen. When the LEDs are located at the edge of the screen (Edge LED), a television can be slimmer as it saves space. However, dimmable zones are relatively large. When you have a television picture with both bright and dark areas, the TV must make a compromise. Sometimes black looks a little too bright. LEDs that are placed directly behind the pixels (Full LED) solve that problem: They use local dimming to dim just the dark areas of the screen, thereby improving the screen’s contrast. You can recognize these televisions by their thicker housing.

OLED and Quantum Dot

OLED combines both advantages: These screens are ultra-flat because their pixels emit the light themselves – the LEDs in the background are no longer needed. This technology delivers the maximum contrast because each pixel can be controlled individually. OLED televisions don’t quite reach the brightness of modern LCD devices, however. If you want to watch TV in the middle of the day in a sun-drenched living room, you should take this into account. Maximum brightness is also important for programs transmitted in HDR. Brightness is specified by the manufacturer in candela per square meter (cd/m2) or nits. The brightest LCD TVs reach 2000 nits, whereas OLED devices reach about half that.

Color quality

Brightness and contrast are only one piece of the puzzle. At least as important is a television’s color reproduction. Televisions with traditional LEDs are at somewhat of a disadvantage as they neglect parts of the color spectrum. The electronics in the television must compensate for this. In better quality TVs, manufacturers rely on quantum dots : Tiny nanoparticles in the backlighting raise the color reproduction to that of an OLED display. However, picture quality depends on additional factors, including the signal processing in your device. It’s definitely worthwhile to compare televisions at a specialist dealer.

Ultra-sharp and crisp

Ultra HD marks the beginning of a new era of television. UHD signals have four times the resolution than older signals (below). Some manufacturers call their UHD technology 4K. And the next generation, 8K, is already coming up. The high pixel count allows for larger screens and a shorter viewing distance: You can sit closer to the television without seeing any blur or pixel patterns. Color reproduction is improved because the image signal contains more information: Instead of 16 million colors, there are now over one billion. UHD signals are provided by television stations, streaming services and Ultra HD Blu-rays. But digital photos and smartphone videos also look better on UHD TVs.

Increased contrast

TV programs with an extended contrast range (High Dynamic Range) provide an additional boost in quality. HDR signals convey more details in dark and bright scenes, resulting in a crisper and more natural picture. Unlike Ultra HD, there are several different standards. HDR-capable TVs must be able to recognize and process these signals to display the picture at full quality. HDR 10 can be displayed on all HDR-capable devices. This has been the standard used by Blu-ray and the Internet for a long time. Television stations use HLG (Hybrid Log Gamma) for transmission. And then there is HDR10+ and Dolby Vision: both of these systems continuously adjust their contrast settings based on the program content, ensuring an optimal picture in every scene.

A wide variety of programs

The range of television channels is huge, from a few dozen channels available via an antenna to many hundreds of channels available via satellite. Some of them are free. The rest is available in an encrypted form to paying customers – such as the HDTV channels provided by private broadcasters or pay TV services such as Sky.

Upgrade

Special technology is required in order to receive and watch encrypted channels. This may be built into the device, in which case you only need a subscription card to unlock it, or it may be added by using a module. Almost all televisions have a port on the housing that allows this: the common interface. Some televisions have two, allowing several subscriptions to be used simultaneously.

Simultaneous channels

How a television receives a program depends on its built-in technology: It needs a separate receiver for each signal. Twin-tuners can display one program on the screen and simultaneously record another on a hard disk.

More than just a television?

Good picture quality is important. However, the other features built into televisions can influence your viewing pleasure equally. Some features, like a twin-tuner, USB recording or a wireless connection are widely available. Other features are only available on certain brands.

Exclusive features

One exclusive extra is an LED light that illuminates the wall behind the TV and automatically changes color to match the on-screen content. However, most of these technologies are rather more hidden. Some TVs can use wireless speakers or provide surround sound. Some models switch channels amazingly fast, while others can transmit signals to second and third TVs within the house (TV>IP).

Ports

The High Definition Multimedia Interface port, HDMI for short, is the most important port on a television. It connects the TV to a game console, Blu-ray-player, AV receiver and more. All modern home cinema devices are equipped with a HDMI port. It’s a good idea to make sure your television has more than one. For UHD and HDR , you’ll need HDMI version 2.0 or higher. Your television should also support the HDCP 2.2 copy protection technology. Models with the official Ultra HD logo meet this requirement. However, this symbol says nothing about the picture quality. That’s why there is another manufacturer-independent label: Ultra HD Premium. It is used to identify televisions that meet particularly high standards.

Media

Even the smallest televisions now have a USB port. This allows you to display photos and videos from external devices on your screen. If you have a smart TV, you can do this via your home network, where the TV can be reached wirelessly or via a LAN cable. The advantage: you no longer need to copy your photos to a USB stick. Your TV can fetch them directly from your smartphone or WiFi-enabled digital camera. This is the same for playing movies and music from a media server. And then of course, there is the internet with its online video platforms, streaming services and cloud storage. There are apps for many of these services, but they are not necessarily available on all televisions. The choice depends on the brand of television. Do you subscribe to an online service that your favorite TV doesn’t support? No problem: you can usually add the missing service via a streaming stick or a player attached to the TV’s HDMI port. These inexpensive devices can be used to add these features to older televisions without networking and smart features.

Smart Home

Some televisions are additionally useful around the house. They can show you images from surveillance cameras, the contents of your refrigerator, or the progress of that roast in your oven. Some models can even take control of smart devices: using an internal or external control device, for example, they can turn lights on or off, or regulate your heating. This means that no one must reach for their smartphone while watching TV – the TV remote control can be used instead.

Beautiful design

Interior designers have long dreamed of TVs that hang on the wall like picture frames. With modern display technology, this is becoming a reality: OLED screens are so flat that they are hardly noticeable from the side. The thinnest require neither a base, nor a mounting device: magnets hold them directly against the wall. Manufactures of some LCD devices supply gapless mounts to achieve a similar effect.

Frameless

Where wide plastic or aluminum frames used to dominate television displays, there is now only a narrow edge. The picture is no longer limited, opening up new design possibilities. Anyone buying a television today not only has a choice of flat or curved displays, they can choose from any number of housing shapes and materials.

Luxurious furnishings

Real wooden surfaces and high-quality fabrics are moving televisions out of their technology corner, transforming TVs into furnishings that are worth being seen. Manufacturers are also paying more attention to the back of the device. This is almost a necessity in light of the increasing screen sizes. A 55 inch diagonal is more easily concealed when it is as an attractive piece of furniture.

Artistic

For wall-mounted devices, a gallery mode completes the illusion of a picture on the wall. It can display your favorite photos or paintings complete with a digital mat. Some TV manufacturers provide photos of works of art from renowned galleries like the Prado in Madrid, or the Victoria and Albert Museum in London as downloads. If your TV comes with a removable frame in a variety of colors, it is hardly distinguishable from the real work of art. Devices with a liquid crystal display are particularly suitable for use in galleries as they are immune to image burn-in. On OLED screens, still images can leave slight shadows after several hours. However, this hardly ever happens in practice: Manufacturers use special technologies to erase such traces, or prevent them from forming in the first place